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The mathematics of changing one's mind: John Allen Paulos reviews 'The Theory That Would Not Die'

MIND-CHANGING MATHEMATICS: John Allen Paulos reviews Sharon Bertsch McGrayne's The Theory That Would Not Die, subtitled – perhaps fittingly, in an age when subtitles have become breeding grounds for circumlocution – "How Bayes’ Rule Cracked the Enigma Code, Hunted Down Russian Submarines and Emerged Triumphant From Two Centuries of Controversy."
Bayes’s theorem, named after the 18th-century Presbyterian minister Thomas Bayes, addresses this selfsame essential task: How should we modify our beliefs in the light of additional information? Do we cling to old assumptions long after they’ve become untenable, or abandon them too readily at the first whisper of doubt? Bayesian reasoning promises to bring our views gradually into line with reality and so has become an invaluable tool for scientists of all sorts and, indeed, for anyone who wants, putting it grandiloquently, to sync up with the universe. If you are not thinking like a Bayesian, perhaps you should be.
Apparently it's actually been rather handy, despite its initial appearance of uselessness.
McGrayne devotes much of her book to Bayes’s theorem’s many remarkable contributions to history: she discusses how it was used to search for nuclear weapons, devise actuarial tables, demonstrate that a document seemingly incriminating Colonel Dreyfus was most likely a forgery, improve low-resolution computer images, judge the authorship of the disputed Federalist papers and determine the false positive rate of mammograms. She also tells the story of Alan Turing and others whose pivotal crypto-analytic work unscrambling German codes may have helped shorten World War II.
Mathematics has never been a point of great interest for me, so I'll leave the probability work to you. Although, for those of us considered somewhat less than mathematically inclined, McGrayne is quick to include simple examples, retold skilfully and concisely by Paulos. Take a look at the full article.